1. The problem statement, all variables and given/known data A student standing on top of a cliff drops a rock down below into the water and hears it splash 3 seconds later. The speed of sound is 330m/s, what is the height of the cliff 2. Relevant equations v= d/t v2 = v1 + at d = v2-1/2 at2 d = (v1 + v2)t v2 squared = v1 squared + 2ad d = v1t + at2 3. The attempt at a solution when I first saw this, I thought of echos v=d/t 330 = d/3 d=990 and then divide by two since echo d= 990/2 d= 495 however, that is horizontal distance not vertical, so I listed my knowns but am unsure as what to do with the 330 m/s knowns for rock v1= 0 (since he dropped the rock) v2= a = -9.8 m/s2 t = 3s d = knowns for speed of sounds v= 330 m/s t = 3s d= ? then setting the distance of both of these equal to each other and solving for d?